Question

F(x)=-2x^2+4x+5
Find the critical numbers

Answer 1

To find critical points, take the first derivative and set it equal to zero:

f(x) = -2x^2 + 4x + 5

f'(x) = -4x + 4

-4x+4 = 0

-4x = -4

x = 1

Critical point at x = 1

Alternatively, if you mean zeros, or where the x intersects, you can use the quadratic equation.